Inhibitory Roles of Nigella sativa seed extracts on in vitro glycation and aggregation

Background: Glycation is the multi-step process wherein the carbonyl group of glucose reacts with the amino group of other nitrogen-containing compounds like proteins and DNA. This interaction leads to the generation of harmful metabolites commonly known as advanced glycation end products (AGEs). These AGEs have been implicated in various diseases such as cataracts, diabetes, and Alzheimer's. Objectives: The aim of the present study was to check the effect of Nigella sativa seed extracts on glycation and aggregation and for this purpose, two proteins (bovine serum albumin [BSA] and hemoglobin) and two sugars (glucose, and ribose) were selected. Materials and Methods: The amount of glycation mediated products was measured by established methods such as browning, nitroblue tetrazolium (NBT) assay, carbonyl content, and aggregation assays in the presence or absence of extracts (1 mg/ml). The effect of extracts was also checked on glycated DNA by agarose gel electrophoresis. Results: Analysis of results indicates that extracts (1 mg/ml) significantly prevented the generation of early products up to 30.57% (BSA-Rib) and 64.90% (Hb-Glu). The AGEs formation was also suppressed in different glycation systems up to 60.76% (BSA-Glu), 30.79% (BSA-Rib) and 10.74% (Hb-Glu) in the presence of extracts. There was also a decrease in the level of glycation-mediated protein aggregation. Seed extracts were able to prevent the glycoxidative damage of DNA. Conclusion: It can be concluded that black cumin seeds have antiglycating and antiaggregation potential as well as antioxidant properties. Further characterization will help in the identification of active compounds which can be used for the prevention of secondary complications of diabetes and aggregation.